New species of jellyfish is seen at a depth of 812 m – 01/24/2024 – Science

A gelatinous animal, about ten centimeters in diameter. Seen from above, it features two crossed red bands, reminiscent of the famous St. George’s cross, the one printed on flags like that of England. This is the Santjordia pagesia new species of jellyfish or jellyfish, as these animals are also known, described by an international group of researchers that includes a Brazilian supported by Fapesp.

The study was published in the journal Zootaxa and its authors include André Morandini, professor at the Institute of Biosciences at the University of São Paulo (IB-USP) and director of the Center for Marine Biology (CEBIMar), at the same institution.

During the work, the researcher had support from Fapesp, within the scope of the Biota Program.

The other authors are researchers from the Japan Agency for Marine and Earth Science and Technology (Jamstec) and the Okinawa Institute of Science and Technology, both in Japan.

Coming from the Ogasawa Islands, around 460 kilometers south of Tokyo, the jellyfish apparently only exists in the Sumisu Caldera, a structure of volcanic origin, around 10 kilometers long, at a depth of 812 meters.

“It is a very different species from what was previously known of deep-sea jellyfish. It is a relatively small animal, while others from this type of environment tend to be much larger. The reddish color in the stomach is probably related to the capture of food”, he explains. Morandini.

Since jellyfish are transparent, the strong color in the digestive system prevents bioluminescent creatures from being seen when swallowed and attracting the attention of predators. Bioluminescent animals are those that produce their own light, quite common in deep, dark waters.

The red cross inspired the name of the genre, also new. The new species pays homage to taxonomist Francesc Pagès, who recently passed away, and gave rise to a new subfamily, within the Ulmaridae family.

Boiler

Typically, some individuals are collected and analyzed to describe a new species. But the difficulty of collecting and the rarity of Santjordia pagesi allowed one individual to be captured and another merely spotted.

The place where the species occurs can only be accessed on scientific expeditions with cutting-edge equipment, such as remote-controlled submersibles like the Hyperdolphin, which collected an individual in 2002.

No other specimen was even sighted until 2020, when another vehicle, the KM-ROV filmed, but was unable to collect, the second known individual of the species.

“We chose to publish the description and draw attention to the species present in this location, which has a substrate rich in minerals with potential for commercial exploitation. Unfortunately, it is not possible to carry out research in places like this without a partner who has interests of this type”, says the Brazilian researcher.

Because it is so different even from closely related species, researchers believe that the jellyfish may have an arsenal of poisons quite different from those previously known. “Who knows, perhaps it holds secrets that are worth more than all the mineral exploration that could occur in that location?”, Morandini speculates. “All this with the advantage of keeping the species and the place untouched”, he concludes.